This is what the nurse said to me today when I was a bit upset at being told I couldn't have my jab because apparently the dr hasn't put an explicit note saying 8 weekly jabs (even though I've had them 8 weekly since last May) After some arguing and quoting of bnf etc I did eventually get the jab over an hour and half later but it has gone back to my dr to clarify the frequency for future jabs.
Anyway just thought I'd post the comment here for all of us so used to the complete ignorance around b12 to collectively shake our heads at!